$E CKPTLOCK

Function

To reset the checkpoint lock when a member fails holding the lock and normal processing to release the lock has failed. JES2 issues the $HASP264 message to identify the member holding the lock. If the lock is not released, other members in the multi-access spool (MAS) configuration are unable to access the checkpoint data set.

Attention:

Use this command with CAUTION!

Do not issue this command unless directed to by an IBM® service representative.
Use of this command when the failing JES2 address space still exists might cause a system outage.
Never automate this command.

Issue this command only if normal processing has failed to release the lock and only after verifying the state of the member identified as holding the lock. When a member fails, normal processing in JES2 (if the checkpoint lock is on DASD) or normal processing in MVS™ (if the checkpoint is in a coupling facility structure) will typically release the lock. However, this code depends on the status of the JES2 address space which holds the lock.

Before using this command to reset the checkpoint lock, you need to ensure that the JES2 member that holds the lock is no longer active. If MVS (specifically, XCF and JESXCF) still considers the member active, then that is why normal processing has not released the lock. To determine if MVS considers the JES2 member active, issue the following command:

D XCF,GROUP,group,node$member

where

group is the JES2 XCF group name obtained from a response to a $DMASDEF,XCFGRPNM command
node is the JES2 node name obtained from a response to $D NJEDEF,OWNNAME command
member is the name of the member that holds the lock.

Typically, the XCF group name and the JES2 node name are the same. For example if the member is IBM1 and the XCF group name and the JES2 node name are POK the command would be:

D XCF,GROUP,POK,POK$IBM1

Based on the status in the resulting MVS IXC333I message, you can determine if issuing a $E CKPTLOCK command is appropriate. If the status is

FAILED or the member is not defined to the group (IXC326I response), then it is safe to issue the $E CKPTLOCK command
ACTIVE, then further investigation is required.
You must first determine if the JES2 address space still exists. Issue:
```
ROUTE system,D A,JES2
```
where system is the SYSTEM name from the IXC333I message. Note: If the name of your JES2 subsystem is not JES2, use the actual subsystem name in the ROUTE command. If the IEE115I response indicates JES2 NOT FOUND, then it is safe to issue the $E CKPTLOCK command. Otherwise, JES2 is still active and issuing the $E CKPTLOCK command could result in JES2 work queue damage.
Any state other than ACTIVE or FAILED, then JES2 should resolve the condition and resuming normal processing. In this case, do not issue a $E CKPTLOCK command.

Syntax


>>-$E--CKPTLOCK--+----------------------------------+----------><
                 '-,--HELDBY--=--+-memname--------+-'   
                                 +-INITIALIZATION-+     
                                 '-INITI----------'

Parameters

CKPTLOCK

The member to which the entering console is attached attempts to reset the checkpoint lock.

HELDBY={memname|INITIALIZATION|INITI}

Specifies the member that has failed while holding the checkpoint lock.

memname: Specifies the 1– to 8– alphanumeric or special ($, #, or @) character name of the failed member that is holding the checkpoint lock.
INITIALIZATION|INITI: The member failed during initialization before a member name was assigned to it (the $HASP264 message indicates this condition).

Authority Required

This command requires system authority. The description of the $T RDRnn command explains how to ensure that the authority of the appropriate MVS system command group is assigned.

This command requires control security access authority. For a description of assigning command input authority, see z/OS JES2 Initialization and Tuning Guide, SA32-0991.

Processing Considerations

The lock reset should be automatic and you shouldn't have to issue this command. Make sure it's appropriate to use this command as described above.
Issue this command from only one member in the multi-access spool configuration.
If the checkpoint lock is not held by the member specified by memname, JES2 does not reset the lock, but reissues the $HASP264 message. This happens only if you specified an incorrect memname or JES2 previously reset the lock.
If you do not plan to restart the failed member immediately, consider using the $EMEMBER(member) command to warm start it if your MASDEF specifications do not already automatically perform this function.

Note: To determine your installation's processing environment, consult your system programmer.

Scope

Single member. The values supplied for this command will be in effect for this member only.

Messages

The $HASP000 message indicates the command was accepted.

Example

 1   $e ckptlock,heldby=sysa

  $HASP000 OK

JES2 resets the checkpoint lock that is held by the failed member identified as sysa.